Battery life on the new BLU Advance 5.0 HD

I just got this phone a couple of days ago, and everything seems to be working just fine (love Marshmallow), but one thing I've noticed is that the battery life seems to be lacking big time, with my previous phone (the BLU Advance 5.0, the one I got now is the new version called BLU Advance 5.0 HD) I could go a couple of days, sometimes even 3 days between charges (I had most of its background services/apps disabled, that's why it lasted so much for a low end phone), with this one, I have it setup up exactly the same way (most of the background stuff disabled) but the battery is definitely wearing off much much faster.

Is there something new in Marshmallow that's not present in 5.1 that's causing this? what should I be checking out/monitoring?